| Description: |
Prostaglandin E2 is a hormone-like substance that participate in a wide range of body functions such as the contraction and relaxation of smooth muscle, the dilation and constriction of blood vessels, control of blood pressure, and modulation of inflammation. |
| Target: |
EP2 Receptor
Human Endogenous Metabolite |
| In Vivo: |
PGE2 (0.3 μg/k, i.p.) significantly reduces the number of peritoneab macrophages undergoing phagocytosis of the methacrybate microbeads in rats[2]. PGE2 (0.1 mg/min, i.a.) increases renal blood flow. PGE2 produces a biphasic change in renal vascular resistance, vasodilatation starts at 0.01 mg/min and is maximal at about 3 mg/min, while at the highest dose used (20 mg/min) PGE2 induces renal vasoconstriction[3]. |
| In Vitro: |
PGE2 shows inhibition of IL 2 production in the mixture of irradiated and nonirradiated T lymphocytes. PGE2 (0.1-10 μM) dose-dependently inhibits the production of IL 2. PGE2 acts during the inductive phase of activation of suppressor cells. Preincubation of T lymphocytes with PGE2 induces cells that suppress IL 2 production and PHA proliferation[1]. |
| Cell Assay: |
Lymphocytes in CM (1×106 cells/mL) are ditributed in microculture plates (100 μL) in triplicate in the presence of PGE-treated T cells or medium-treated T cells and stimulated with PHA-P at various mitogenic doses. After 72 hr, cultures are pulsed with 1 μCi [3H]thymidine per well (specific activity 5 Ci/mM) for 16 to 18 hr, collected with amicroprecipltator, dried, and counted in a liquid scintillation counter. |
| Animal Administration: |
Male Sprague Dawley rats (200-250 g) are used throughout the study. For 3 consecutive days rats in the experimental groups receive a daily intraperitoneal injection of either PGE2 (0.3 μg/kg body weight (BW)), the prostaglandin inhibitor mecbofenamate (10 mg/kg BW) or the prostaglandin precursor arachidonic acid (0.3 μg/ kg BW). To determine whether or not 0.3 μg/kg BW of a fatty acid produces nonspecific effects, the biologically inactive fatty acid 11, 14, 17-eicosatrienoic acid is also administered to a group of rats. Rats in the control group receive an equivalent volume (2.0 mL/kg BW) of the vehicle. On the third day, 3 mL of a suspension containing 1.2×106 fluorescent methacrylate microbeads/mL of PBS are injected intraperitoneally (ip) into each rat. Six hours later all animals are given ip a regular dose of their respective treatment. Peritoneal exudate cells are harvested 19-22 hr later. |
| References: |
[1]. Chouaib S, et al. The mechanisms of inhibition of human IL 2 production. II. PGE2 induction of suppressor T lymphocytes. J Immunol. 1984 Apr;132(4):1851-7.
[2]. Fernandez-Repollet E, et al. In vivo effects of prostaglandin E2 and arachidonic acid on phagocytosis of fluorescent methacrylate microbeads by rat peritoneal macrophages. J Histochem Cytochem. 1982 May;30(5):466-70.
[3]. Haylor J, et al. Renal vasodilator activity of prostaglandin E2 in the rat anaesthetized with pentobarbitone. Br J Pharmacol. 1982 May;76(1):131-7. |
